NEMESIS: A Novel Evaluation Platform for Measuring Endurance of Byzantine Fault-Tolerant Systems under Injected Stressors

• Applicant: Dr. Christian Berger
• Subject Area: Security and Dependability, Operating-, Communication- and Distributed Systems
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 580170010

The project’s overall goal is to establish a foundational research framework for the systematic evaluation of novel Byzantine Fault-Tolerant (BFT) protocols under realistic and adversarial conditions. Yet, existing evaluation methods are often too protocol-specific or offer only limited help to explore more complex attack scenarios. For this purpose, the proposed project follows three main research objectives:(I) Designing a realistic, scalable and reproducible evaluation platform:The project investigates how to design a modular platform that combines the realism of emulation (execution of unmodified protocol binaries) with the scalability and determinism of simulation methods, thus following a hybrid emulation/simulation approach. The goal is to support heterogeneous protocol implementations (Rust, Go, Java, C++), enable reproducible re-execution through suitable techniques, and model realistic WAN conditions using real-world latency/bandwidth statistics. This platform provides the underlying technical foundation for controlled, high-fidelity evaluation.(II) Exploration of novel search techniques for the strategic adversary:The project develops systematic, protocol-aware search techniques for generating coordinated Byzantine attack strategies. These strategies exploit protocol states (i.e., locked/committed blocks, pending messages types) and execution phases to explore semantic execution paths beyond the reach of existing random or pre-scripted approaches. The project focuses on DAG-based BFT protocols, whose asynchronous, parallel design might expose new vulnerabilities such as volume-based and resource exhaustion attacks that exploit flaws in state persistence or garbage collection. The goal is to research how to effectively traverse the large search space of coordinated behaviors across different protocol implementations and whether a state-aware, guided approach can identify more vulnerabilities, including more subtile ones that lead to performance degradation.(III) Bridging the gap between formal liveness and practical usability:Our third goal extends the platform to also detect subtile liveness issues. These could easily arise under realistic conditions, especially under higher network delays, disruptions, or resource constraints. We want to allow for a systematic detection of degraded states in which the system may not formally violate a liveness property but is still effectively unusable because of issues like stagnating block commitments or excessive latency. Overall, this project intends to bridge a gap between formal correctness guarantees and the operational usability of BFT systems by developing techniques that can make practically relevant liveness problems observable and measurable.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr.-Ing. Rüdiger Kapitza